Apparatus for inserting support wires in lamp stems



Apxfil 1, 1952 f Filed Dec. 6, 1946 c. TlTus E-rAL 2,590,904

APPARATUS PoR INSRRTING SUPPORT WIRES 1N LAMP sTEMs 5 Sheets-Sheet l W M/ AHorn e y April 1, 1952 c. TITUs t-:TAL 2,590,904

APPARATUS FOR INSERTING SUPPORT WIRES IN LAMP STEMS Filed Dec. 6. 1946 3 Sheets-Sheet 2 INVENTORS Charles L. Tus

Edwin W. Barrer April 1, 1952 c. L. 'nTus x-:T AL

APPARATUS FOR INSERTING SUPPORT WIRES IN LAMP STEMS Filed DeG. 6, 1946 3 Sheets-Sheet I5 Ilil,

S R T www M w NH r Y ET@ o V .B J 1N.L, Mm sw mm uw hd CFL Y B Patented Apr. l, 1952 UNITED STATES iDTENT OFFICE APPARATUS FOR INSERTING SUPPORT WIRES IN LAMP STEMS- Application December 6, 1946, Serial No. 714,356

2 Claims.

This invention relates to a machine for fabricating elements for lamps and thermionic devices such as stems for lamps and is particularly directed to a mechanism for assembling supporting wires to a stem member such wires being useful to support a filament or other element.

It is an object of the invention to provide an apparatus for rapidly and accurately inserting support wires in stem assemblies.

A further object of the invention is to provide a mechanism for the purpose specified in which adjustments are readily made to produce and insert support wires of various lengths.

A further object of the invention is to provid a magazine type wire feed in which areel of wire provides the source of supply and in which the wire under complete control is fed in straightened condition to its working position.

A further object of the invention is to provide means for readily inserting full reels of wire when the wire is exhausted from the reel which is being used.

Other objects and features of the invention will more fully appear from the following description and will be particularly pointed out in the claims.

The mechanism embodying the invention is provided with a plurality of wire feeding devices arranged radially about the axis of the stem to be processed. The stem desirably being held in a holding device upon a conveyor means mounted upon the main machine frame and described in more detail in the co-pending application, Serial No. 637,440, filed December 27, 1945, by Roland M. Gardner, Stanley J. Gartner and Edwin W.

Barrett having the title Automatic Lamp Stem Fabricating Apparatus.

The wire feeding devices are provided with replaceable reels or spools of wire to provide a source of supply. The feeding mechanism measures the correct length cf wires and moves them into working position with their inner ends at the stem axis and overlying a button forming member having a molding cavity therein.

While the wires are in this position the complete mechanism is raised upward against the end of the exhaust tube extending downward from its holder cn the conveyor. The end of the exhaust tube has been softened in the conventional manner by a gas flame and the upward stroke of the mechanism' is adjusted to cause sufficient glass to accumulate in molding to form a filament supporting button. In the forming of the button the glass fiows around and anchors the ends of the support wires in the button.

Immediately after the button forming opera- 2 tion the wire feeders are moved outward and thus draw from the reels suicient wire to form the lament supports and finally the supports are out to required length.

To provide a better understanding ofthe invention a particular embodiment will be described and illustrated in the drawings in which:

Figure 1 is a vertical cross sectional view of the apparatus;

Figure 2 is a plan view of the apparatus;

Figure 3 is an enlarged detail side elevation of a wire feeding unit;

Figure 4 is a View of the upper portion of the mechanism showing a wire feeding device in retracted position;v 1

Figure 5 is an enlarged sectional view of the end portion of a stem and filament supporting button;

Figure 6 is a detail illustration of the means for cutting off the wires;

Figure 7 is a perspective view of the completed Lipper or lament supporting portion of a stem; and

Figure 8 is an enlarged sectional view of a portion of the wire feed.

The mechanism embodying the invention is mounted upon the frame of an automatic mazchine for fabricating a lamp stem, such -as the machine described, in the copending application above referred to.

Desirably the mechanism is secured to the platen I of the machine and is supported by a bracket 2 adjustably positioned upon the platen.

The bracket 2 is provided with a vertical aperture 3 within which a sleeve 4 of a vertically moveable carrier or platform 5 is accurately fitted.

One portion of the support wire inserting mechanism is mounted on the carrier 5 while another independently moveable portion thereof -is mounted on a vertically moveable shaft 6 accurately fitted within the sleeve 3. The shaft 6 has mounted thereon an actuator 1 having Wire feeding cams 8 thereon and also cutting olf knives to cut the support wires to their proper length.

The carrier 5 on the sleeve 4 has mounted thereon a plurality of wire supplying units to be described in detail hereinafter.

To produce the required sequence of operations to insert and cut oif a plurality of support wires the carrier 5 and the actuator l are actuated by a pair of cams 8a: and 9 mounted upon the cam shaft lo. The shaft l0 is driven in timed relation to the conveyor mechanism not shown which successively feeds stem assemblies into position for receiving their support wires.

To provide for the proper function of the mechanism, the sleeve 4 and the shaft 6 must be held against rotation. This may be done in any suitable manner. As shown in the drawing the sleeve 4 has secured to its bottom end a collar I I to which in turn is secured a guide bar |2 disposed in parallel alignment to the axis of the sleeve. The upper end of the bar I2 is received in a slot I3 formed in the bracket 2. The bar I2 fits closely in the slot and permits vertical movement of the sleeve but prevents any rotative motion thereof.

The bar I2 extends downward and has connected thereto an actuating link |4 which in turn is connected to a lever |5 fulcrumed on the shaft I6. The lever I5 is provided with a cam follower roll I1 which rides upon the cam 9. The cam is so shaped that throughout a complete rotation of the shaft I the frame and its component parts will move up and down in proper timing and sequence.

The shaft 6 has secured to its lower end a collar I8 which extends toward and closely embraces the sides of the bar I2 to slide thereon when relative movement occurs between the sleeve 4 and shaft 6. The collar I8 thus serves to prevent rotation of the shaft 6.

The shaft 6 is vertically reciprocated by the cam 8a: on the shaft I0. The lower end of the shaft 6 is provided with an adjustable abutment I9 against which a roll 20 engages. The roll is mounted upon the outer end of a lever 2| fulcrumed upon the shaft 22 and provided with a follower roll 23 rotatably mounted on the lever between its fulcrum and the roll 2U. The roll 23 rides upon the periphery of the cam 8x. The downward travel of the shaft 6 is powered by one or more springs 24 connected at one end to the collar |8 and at their other end to an arm 25 rigidly fastened to the shaft I6. The spring maintains the roll 23 upon the cam and causes the shaft 6 to move in accordance with the cam contour which is designed to produce the correct motion and timing of the actuator 1.

'I'he downward travel of sleeve 4 carrying the frame 5 is powered by the spring 26 connected at one end to the lever I5 and at its other end to an arm 21 rigidly secured to the shaft 22. The spring 26 also maintains the roll l1 in contact with its cam 9.

In the particular embodiment of the invention shown means are provided for inserting three support wires 28 in the button 29 of the upper portion of the stem 30. However, any desired number of wires may be provided by using the required number of wire supplying units. As

shown in Figure 2 three such units are provided= radially arranged at equally spaced angles about the axis 3| of the stem. Any combination of angles may be used.

The wire supply units are movably mounted on carrier 5 in any desired manner. Accurate alignment of the units are desirably maintained by a tongue and groove connection 33 between the carrier 5 and a supporting body 34 for each unit. Each of the units are alike so a single unit only will be described. The body 34 extends upward and has a horizontally disposed guideway 35 Within which is received the wire supply unit which is provided with a slide member 3S moveable in the guideway 35.

Wire supplying elements are removably mounted upon the supply units and move therewith. Wire for the supports 28 is supplied from a wire spool 31 upon which a mass of wire is wound. The spool is rotatably mounted upon a supporting framework 38. The frame 38 is secured to the units in any suitable manner as by the screw 39 which passes through the slide 36 and has threaded engagement with the frame 38. To maintain rigid alignment between the members a plate 40 is closely fitted to a slot in the frame 38 having one of its edges tightly engaging an edge of the slide and held in position by the screws 4| received in the frame. The frame 38 desirably is provided with a housing 42 within which is received a brake drum 43 secured to a shaft 44 upon which the spool is mounted. The drum is provided with a brake band 45 anchored at one end to a spring 46 and to an adjustable arm 41 at its other end. By adjusting the arm 41 more or less of the tension of the spring 46 is applied to the band to vary the drag on the wire when it is drawn from the spool and also the brake prevents over travel of the spool. The frame 38 is provided with a threaded aperture to receive a stop screw 48 which determines the extent of inward travel of the wire in a manner to be described.

A wire guiding and straightening unit 49 is secured to the fiat top surface 50 of the supply unit over which the wire travels. The surface 56 is disposed in a plane substantially tangent to the periphery of the spool 31. The wire must also be maintained in a straight line radially disposed to the axis 3| of the stem. To accomplish this the wire is lead between two rolls 5| vertically pivoted upon the surface 50. Desirably the rolls are sunken slightly below the surface 53 to prevent the wire from getting beneath the rolls as shown in Figure 3. The rolls 5I align the wire in a vertical plane while another roll 52 acts to hold the wire upon the surface 59.

The roll 52 is horizontally pivoted in a block 53 which is secured to the surface 50. A slot or aperture is provided in the end of the block adjacent the spool to permit the wire freely to engage the roll 52. From the roll 52 the wire passes through a guiding slot 54 formed in the bottom surface of the block and extending radially toward the axis 3|.

A one way friction device is desirably provided to maintain the wire in a desirably taut condition. Such a device may have any suitable construction. As shown herein the block 53 has formed therein a chamber 55 open at its bottom to expose the wire and having a top wall 56 disposed at an angle with respect to the surface 59 which converges toward the spool 31. A short friction roll or cylinder 51 is received in the chamber 55 and has a spring 58 engaging and urging the roll against the angular wall 56 and the wire. Obviously the wire when pulled to unroll it from the spool is not resisted by excessive friction. However, any tendency for the wire to be pulled in the other direction tends to wedge the roll 51 against the wire and thus lock it against retractive movement. The friction at the spool combined with the action of the roll 51 maintains the wire under control at all times.

The inner end of the block 49 is bored in a direction parallel to the wire to receive the shank of a wire feeding finger 59. The nger 59 desirably has a flat top surface 60 in line with the surface 59. The wire is fed along the surface 60 or desirably in a groove 6| cut in the suiface. A flexible cover plate 62 is also provided which acts to maintain the wire in its groove 6|. The finger cover 62 is held against the wire by a screw 63 upon which the cover also pivots to permit it to be swung laterally away from the groove E! to facilitate threading the wire therethrough. The position of the iinger with respect to the stem axis 3i is adjusted by varying the degree to which its shank penetrates the aperture in the block t9. The desired adjustment may be maintained by a suitable set screw or other device. The nnger 59 is made relatively narrow at its inner end to permit its close approach to the stem being processed.

It is desirable that means be provided for protecting the surface 5) directly beneath the point where the roll 51 engages the wires. To accomplish this an insert @il of hard material, such as tungsten carbide, is inserted in the block to absorb the pressure on? the wire and prevent excessive wear of the block.

A button forming member G5 is situated upon the stem axis and having its upper rim in the plane of the surface 5t. The member 65 is provided with a molding cavity 66 into which the heat softened end olf the stem Se is forced by the upward movement of the frame 5. The meinber 65 is rigidly received in a supporting bracket 61 extending down to the frame `ii and secured thereto by means of an adjusting device 68 by means of which the member may be accurately adjusted into alignment with the working axis 3| upon which the stems are held.

The wire supplying units are moved toward and from the stem axis by means of actuating levers 69 pivoted upon the members 3d at 1d. The lever 69 has a slot 1'! at its upper end :within which is received a roll x which in turn is rotatably mounted upon the slide 3G. Rotation of the lever E9 is thus transmitted to the slide.

The levers 69 are actuated by the cams S vertically adjustable upon the actuator 1. As in the foregoing description only one of the cams 8 and levers 69 will be described.. The cam 8 has an elongated aperture 12 therein through which an attaching screw 13 passes desirably the head orf the screw is countersunk into the cam.

Vertical adjustment of the cam is obtained by means of screw lil which abuts the bottom edge of the cam. rl'he adjustment of the screw 14 is locked by a nut l5. The lever t9 is provided with a follower roll 16 which is engaged by the cam during the machine cycle to actuate the wire supplying unit.

Suitable means are provided for cutting `01T the wires to a predetermined length after they have been secured in the button 29. As shown herein the cutting oir means comprises Ia pair of shearing members 11 and 18. The member 18 is pivoted at its bottom end to the bifurcated end of a supporting member 19 which in turn is rigidly secured to the top of the head 1. The member 11 is pivoted to a supporting bar Se which in turn is received in an aperture in a boss 8i on fthe upper portion of the body member 3d. The boss 8l is constructed to clamp the support bar 8|) through the medium or a set screw 32.

The members 1Q and te are provided with means for Iadjusting their position along a radial line from the axis 3l this adjustment provides for cutting the support wires to different lengths as required.

The members 11 and 155 slide upon one another and are provided with cutting edges 83 and 8d which desirably are made or hard material such as tungsten carbide. The two cutting members are held in shearing relation by means of a connector pin one end of which is xned in the member 18 while its other end projects through a slot 86 in the member 11 and extends beyond the slot B6 and has thereon a compression spring 81 one end of which engages member 11 and its other end bears against a washer 88 held in position on the pin 85 by a key or any suitable means. The -two members 11 and 18 are thus held in contact by the tension of the spring 81 and are :free to move vertically with respect to each other and in so doing the pin 85 moves in the slot 86.

The throw orf the cam 8 is such that at the maximum upward movement of the head 1 the cutting edges 83 and 84 shear on" the wire `which passes through the bifurcated upper end of the member 11.

Desirably the spoools of wire 31 are protected from rfalling glass particles or other foreign matter by a guard 39 secured in position above the spools.

The frame 5 is spiderlike in form as shown in Figure 2 having as many arms as there are wire supplying units. Similarly the head 1 also has a plurality of arms each arm having the cams 8 and cutter supporting members 19 thereon.

The cams 8 act to move the arms 69 in their outward travel while their inward travel is powered by a spring 90 anchored at one end to the body members 34 rand at its other end to pro jections Si on the arm 69.

The operation of the mechanism is as dollows. Starting with that condition where one stem has been supplied with support wires and they have been out to length by the cutter members, at which time the frame 5 and head 1 are at the top of their movement and the slides 36 are completely retracted outward. Then continued rotation of the cams 8:0 and 9 cause the springs 24 and 25 to act to move lboth the head 1 and frame 5 downward to their lowest position and during such downward motion the springs 90 move the slides 36 and the wire supply units inward to feed another set of support wires into position with their inner ends close to the axis 3l.

During this down travel the cams are so designed that the head 1 moves farther than the frame 5 causing the cams 8 to ride away from the rolls 16. The limit of inward travel is determined by the engagement of the stop screw 48 with a stop boss 93 on the member 34.

While the mechanism is in its down position another stern is fed into position on the axis 3|. The new stem has an unformed tube 92 projecting down therefrom. This tube may be an extension of the stern exhaust tube. Continued rotation of the cams causes the feed 1 and frame 5 to travel upward until the button former 65 engages the softened end of the tube 92 to form the button and anchor the ends of the support wires in the glass. The end of the tube is softened by one or more gas burners S4 or in any suitable manner. At this time the frame 5 has reached its maximum upward travel. The actuator 1 however continues upward and its cams 8 act to swing the arms 69 outward which moves the wire supplying units outward. The inner ends of the wires are anchored in the stem at this time. As the wire supply units move outward therefore the required amount of wire is drawn from the spools 31.

The iinal upward travel of the actuator 1 causes the cutting members 11 and 1B to cut the wires 28 to their correct length thus completing 7 the functional cycle of the device. The stems then travel to other stations where a filament is mounted on the Wires and the stem is otherwise completed and ready for insertion in an envelope.

As pointed out above the shear members are adjusted to cut the support wires to required length but this length is in turn dependent upon the amount of wire drawn from the wire spool which is determined by the throw of the arms 69. and the position ofthe stop screw ri. To secure the desired length of the support Wire therefore the cams 8 are adjusted by means of the screws 'M and the stop screw 48 is properly adjusted to cooperate with the cutting off position of the shear members 11 and 18. It may also be desirable totadjust the member 59 to insure its proper position at the inner end of the travel of the wire supply units to that point where it will not engage the member 65 and yet be closely adjacent to it to adequately support the Wire.

The wire reels 3'! are rim like in structure having space thereon for the mass of wire. The reels are detaehably received upon the spokes of a spider 95, which in turn is connected to the reel braking device.

The spokes of the spider receive the reel which is held thereon by spring fingers 96 which frictionally engage the inner peripheral face of the reel. Thus when wire is exhausted from a reel aV full one is readily substituted.

In many types of lamp stems the portion to be formed into a filament supporting button is a tube usually a continuation of the exhaust tube of the lamp. When this is so the formation of the button tends to trap some air or other gas in the tube between the lamp stem press and the button. This trapped gas may cause trouble in the subsequent operation of the lamp. It is desirable therefore that this gas be vented to insure that it will be removed when the lamp is pumped out. To do this the button former 65 is provided with a pointed piercing member 91 which forms an opening through the button and into the tube simultaneously with the formation of the button.

We claim:

1. Apparatus for fabricating a button on a lamp stem and inserting filament support wires therein said apparatus comprising: a carrier; a button-forming member mounted on said carrier; means for effecting reciprocating movement of said carrier in a vertical plane; filament support wire supply units mounted on said carrier; wire feeding actuators mounted for reciprocation vertically and coaxially with said carrier; means for effecting reciprocating movement of said actuators in a vertical plane; and means, actuated by the reciprocating movement of said actuators in a vertical plane, for effecting reciprocating movement of said filament support wire supply units in a horizontal plane.

2. Apparatus for fabricating a button on a lamp stem and inserting filament support Wires therein, said apparatus comprising: a carrier; a button-forming member mounted on said carrier; means for effecting reciprocating movement of said carrier in a verticalplane; filament support wire supply units mounted on said carrier; wire feeding actuators mounted for reciprocation vertically and coaxially with said carrier; means for effecting reciprocating movement of said actuators in a vertical plane; means, actuated by the reciprocating movement of said actuators in a vertical plane, for eiecting reciprocating movement of said filament support wire supply units in a horizontal plane; and a plurality of wire-shearing members, one of each of said members being mounted on each of said actuators and the other of each of said members being mounted on each of said filament support wire supply units.

CHARLES L. TITUS. EDWIN W. BARRETT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,128,120 Fagan Feb. 9, 1915 1,220,836 Frech et al Mar. 1'7, 1917 1,238,575 Schluter Aug. 23, 1917 2,163,071 Stringer June 20, 1939 FOREIGN PATENTS Number Country Date 519,952 Great Britain Apr. 10, 1940 

